So, explain to me again why the answer to all apocalypses is to kill and torture teenagers?

The last of a literally dying breed – the post-apocalyptic teen-killing dystopia franchise – bows out with a noisy whimper this week with the interminably-long, narratively inane Maze Runner: The Death Cure. The Hunger Games series managed to crawl to the finish line before it, and the final chapter of the Divergent series, Ascendant, was plucked from production and “repositioned” as a TV project (about which we’ve heard relatively little).

If the genre is well and truly dead, Maze Runner: The Death Cure is a fittingly awful nail in its coffin.

Oddly, the series started out in 2014 on an intriguingly mysterious note, almost Twilight Zone-ish in the spareness of its storytelling. The Maze Runner had a handful of amnesiac young people living in a mysterious “Glade,” a domed environment that added new inhabitants every so often. If you tried to leave the Glade through various doors, you were invariably killed by the robot monsters on the other side. Somewhere above, scientists were carrying out a nefarious-looking experiment.

That movie ended with a mass escape, a ravaged environment and almost nothing in the way of answers. It was oddly satisfying.

Answers were to come, of course, and they would be stupid ones. (Also, there would be no more mazes, but plenty of running and shooting.) Seems there was a zombie apocalypse out there (the zombies are called “cranks”), courtesy of a bug so similar to the Rage virus in 28 Days Later, I’m surprised no one was sued.

And our Glade pals, Thomas (Dylan O'Brien), Minho (Ki Hong Lee), Frypan (Dexter Darden) and Newt (Thomas Brodie-Sangster)? They turned out to be part of a series of Mengele-worthy experiments to determine why certain young people were immune to the plague. The proprietor of those experiments: an organization called WCKD (pronounced “wicked!” and not in a good way).

I feel if you just simply asked unaffected teens to help find a cure, maybe gave them free pizza, you could have avoided the trouble of creating a high-tech Potemkin village to stimulate their adrenal glands to secrete hormonal jamba juice. Or something.

As it is, after all the death and destruction therein, the denouement of Death Cure is so absurdly simple, the scientists involved should have discovered it before the first movie even started. (Oh, you need a blood sample? Sure, here you go).

A series that basically devolved into action for its own sake (forget catching up to the plot if you haven’t seen the first two movies), Death Cure opens with a daring attack on a train full of captured kids, Thomas and company, aided by their pals Jorge (Giancarlo Esposito) and Brenda (Rosa Salazar). Brenda was exposed to the virus in the last movie and was expected to be dead by now, but let’s not get ahead of ourselves.

Only partially-successful, the raid fails to retrieve the captured Minho. So naturally, this handful of armed young adults decide to invade an entire city – a walled refuge for the uninfected and the corporate home of WCKD. There they plan to free Minho and maybe get revenge on Teresa (Kaya Scodelario), a Glader who turned traitor in the previous film.

Happily for their seemingly infinitesimal chances of success, they encounter Gally (Will Poulter), a fellow Glader left-for-dead in the first Maze Runner. Actually Poulter left for better movies, including The Revenant, but now that he’s the single star to emerge from the Maze Runner series, he probably got offered a WCKD paycheque.

What can be said about series director Wes Ball is that he has a flair for noisy gun and air battles, pyro, fights, destruction, pursuit and escape. But it signifies nothing if there is no plausible reason for pretty much anything that happens.